The present invention relates to a screen display control system of a data processing device having a multiwindow function and, more particularly, to a screen display control system suitable for application to a teleconferencing system in which a plurality of terminal units (workstations) are connected by a network and the users located at remote positions execute cooperative works such as conferences, meetings, or the like while referring to the common documents displayed on the screen.
In a system in which a plurality of terminal units or workstations are connected by a communication network and a plurality of users can participate in a meeting through terminal screens, as a technique in which the status and information of the conference are displayed in one window, there is a technique disclosed in the literature of "A Teleconferencing Monitor on Computer-Supported Multiparticipants Teleconferencing System ASSOCIA", The Information Processing Society of Japan, the 44th Convention Preprint, 1-271, 1992. The above technique enables participants of the electronic conference to obtain information including names of other participants by utilizing the objects which represent the other participants or documents by using icons on the screen.
In the above technique, however, all of the participants commonly see the information regarding the teleconferencing monitor window expressing a place of the conference. A separate window to prepare documents for a personal work is needed. It is considered that a process to previously register the documents which are used in the conference into the teleconferencing monitor window is needed. The details of the manipulation when the participant wants to bring the document which is suddenly necessary during the conference into the conference are not disclosed in the above technique.